Question

I am trying to figure out how to launch an external editor from within a Go program, wait for the user to close the editor, and then continue execution of the program. Based on this SO answer, I currently have this code:

package main

import (
    "log"
    "os"
    "os/exec"
)

func main() {
    fpath := os.TempDir() + "/thetemporaryfile.txt"
    f, err := os.Create(fpath)
    if err != nil {
        log.Printf("1")
        log.Fatal(err)
    }
    f.Close()

    cmd := exec.Command("vim", fpath)
    err = cmd.Start()
    if err != nil {
        log.Printf("2")
        log.Fatal(err)
    }
    err = cmd.Wait()
    if err != nil {
        log.Printf("Error while editing. Error: %v\n", err)
    } else {
        log.Printf("Successfully edited.")
    }

}

When I run the program, I get this:

chris@DPC3:~/code/go/src/launcheditor$ go run launcheditor.go 
2012/08/23 10:50:37 Error while editing. Error: exit status 1
chris@DPC3:~/code/go/src/launcheditor$ 

I have also tried using exec.Run() instead of exec.Start(), but that doesn’t seem to work either (though it doesn’t fail at the same place).

I can get it to work if I use Gvim instead of Vim, but it refuses to work with both Vim and nano. I think it’s related to Vim and nano running inside the terminal emulator instead of creating an external window.

Answer 1

Apparently, you have to set Stdin, Stdout and Stderr on the Cmd object to os.Std(in|out|err). Like this (assuming that the object is called cmd):

cmd.Stdin = os.Stdin
cmd.Stdout = os.Stdout
cmd.Stderr = os.Stderr

Credit for solving this goes to the guys on #go-nuts on freenode.